Add missing space in code
minor #4419 [DependencyInjection] Add missing space in code (michaelperrin)

This PR was merged into the 2.3 branch.

Discussion
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[DependencyInjection] Add missing space in code

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | all
| Fixed tickets | N/A

That's really a small contribution, but it solves a slight PSR issue.

Commits
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aff9c2c Add missing space in code